A facile fabrication of hierarchical Ag nanoparticles-decorated N-TiO2 with enhanced photocatalytic hydrogen production under solar light

Abstract

The hierarchical Ag NPs with a bimodal size distribution were auto-decorated on the surface of rice-like N-TiO2 (named h-Ag/N-TiO2) by semiconductor-metal double excitation process under solar light irradiation. The photoinduced growth process of self-assembled h-Ag/N-TiO2 and its photocatalytic mechanism of photo-splitting ethanol into hydrogen have been discussed in detail. The synthesized h-Ag/N-TiO2 as a plasmonic photocatalyst for photo-splitting ethanol exhibited a higher hydrogen production rate (4.7 mmol h−1 g−1) than Ag NPs universally loaded N-TiO2 (3.4 mmol h−1 g−1) and pure N-TiO2 (2.1 mmol h−1 g−1). This work presents a reversed photo-induced synthesis strategy to design a stable Ag-TiO2 plasmonic photocatalyst with high photocatalytic efficiency under solar light. A better understanding of this solar light induced self-assembled process for Ag-TiO2 is crucial in developing metal-semiconductor system for solar energy materials.